<template>
  <div class="app-container">
    <h2 style="text-align: center;">发布新课程</h2>
    <el-steps :active="1" process-status="wait" align-center style="margin-bottom: 40px;">

      <el-step title="填写课程基本信息"/>
      <el-step title="创建课程大纲"/>
      <el-step title="最终发布"/>
    </el-steps>
   
<el-form label-width="120px">
  <el-form-item label="课程标题">
    <el-input v-model="courseInfo.title" placeholder=" 示例：机器学习项目课：从基础到搭建项目视频课程。专业名称注意大小写"/>

  </el-form-item>
  <!-- 所属分类 TODO -->
  <el-form-item label="课程分类">
  <el-select
    v-model="courseInfo.subjectParentId"
    placeholder="一级分类" @change="subjectLevelOneChanged">
    <el-option
      v-for="subject in subjectOneList"
      :key="subject.id"
      :label="subject.title"
      :value="subject.id"/>
  </el-select>
  <!-- 二级分类 -->
<el-select v-model="courseInfo.subjectId" placeholder="二级分类">
  <el-option
    v-for="subject in subjectTwoList"
    :key="subject.id"
    :label="subject.title"
    :value="subject.id"/>
</el-select>
</el-form-item>
  <!-- 课程讲师 TODO -->
  <!-- 课程讲师 -->
<el-form-item label="课程讲师">
  <el-select
    v-model="courseInfo.teacherId"
    placeholder="请选择">
    <el-option
      v-for="teacher in teacherList"
      :key="teacher.id"
      :label="teacher.name"
      :value="teacher.id"/>
  </el-select>
</el-form-item>

  <el-form-item label="总课时">
    <el-input-number :min="0" v-model="courseInfo.lessonNum" controls-position="right" placeholder="请填写课程的总课时数"/>

  </el-form-item>
  
<!-- 课程简介-->
<el-form-item label="课程简介">
    <tinymce :height="300" v-model="courseInfo.description"/>
</el-form-item>

  <!-- 课程封面 TODO -->
  <!-- 课程封面-->
<el-form-item label="课程封面">
  <el-upload
    :show-file-list="false"
    :on-success="handleAvatarSuccess"
    :before-upload="beforeAvatarUpload"
    :action="BASE_API+'/eduoss/fileoss'"
    class="avatar-uploader">
    <img :src="courseInfo.cover">
  </el-upload>
</el-form-item>

  <el-form-item label="课程价格">
    <el-input-number :min="0" v-model="courseInfo.price" controls-position="right" placeholder="免费课程请设置为0元"/> 元

  </el-form-item>
  <el-form-item>
    <el-button :disabled="saveBtnDisabled" type="primary" @click="saveOrUpdate">保存并下一步</el-button>

  </el-form-item>
</el-form> 
</div>
</template>
<script>
import course from '@/api/edu/course'
import subject from '@/api/edu/subject'
import Tinymce from '@/components/Tinymce'
export default {
  components: { Tinymce },
    data(){
        return{
            saveBtnDisabled:false,
            courseInfo:{
                title: '',
                subjectId: '',
                subjectParentId:'',
                teacherId: '',
                lessonNum: 0,
                description: '',
                cover: '/static/11.jpg',
                price: 0

            },
            courseId:'',
            teacherList:[]
            ,subjectOneList:[],
            subjectTwoList:[],
            BASE_API: process.env.BASE_API
        }
    },
    created(){
      if(this.$route.params && this.$route.params.id){
        this.courseId=this.$route.params.id
        this.getInfo()
      }else {
            //初始化所有讲师
            this.getListTeacher()
            //初始化一级分类
            this.getOneSubject()
        }
       
    },
    methods:{
      getInfo(){
        course.getCourseInfoId(this.courseId)
        .then(response=>{
          this.courseInfo=response.data.courseInfoVo
          //1 查询所有的分类，包含一级和二级
                    subject.getSubjectList()
                        .then(response => {
                            //2 获取所有一级分类
                            this.subjectOneList = response.data.list
                            //3 把所有的一级分类数组进行遍历，
                            for(var i=0;i<this.subjectOneList.length;i++) {
                                //获取每个一级分类
                                var oneSubject = this.subjectOneList[i]
                                //比较当前courseInfo里面一级分类id和所有的一级分类id
                                if(this.courseInfo.subjectParentId == oneSubject.id) {
                                    //获取一级分类所有的二级分类
                                    this.subjectTwoList = oneSubject.children
                                }
                            }
                        })
                        //初始化所有讲师
                        this.getListTeacher()
        })
      },
        handleAvatarSuccess(res,file){
            this.courseInfo.cover=res.data.url
        },
        beforeAvatarUpload(file){
        const isJPG = file.type === 'image/jpeg'
  const isLt2M = file.size / 1024 / 1024 < 2
  if (!isJPG) {
    this.$message.error('上传头像图片只能是 JPG 格式!')

  }
  if (!isLt2M) {
    this.$message.error('上传头像图片大小不能超过 2MB!')

  }
  return isJPG && isLt2M

        },
        subjectLevelOneChanged(value){
            for(var i=0;i<this.subjectOneList.length;i++){
                var oneSubject = this.subjectOneList[i]
                if(value === oneSubject.id){
                    this.subjectTwoList=oneSubject.children
                    this.courseInfo.subjectId=''
                }
            }
        },
        getOneSubject(){
            subject.getSubjectList()
                .then(response=>{
                 this.subjectOneList=   response.data.list
                })
        },
        getListTeacher(){
            course.getListTeacher()
                .then(response=>{
                   this.teacherList= response.data.items
                })
        },
          addCourse() {
            course.addCourseInfo(this.courseInfo)
                .then(response => {
                    //提示
                    this.$message({
                        type: 'success',
                        message: '添加课程信息成功!'
                    });
                    //跳转到第二步
                    this.$router.push({path:'/course/chapter/'+response.data.courseId})
                })
        },
        //修改课程
        updateCourse() {
            course.updateCourseInfo(this.courseInfo)
                .then(response => {
                     //提示
                    this.$message({
                        type: 'success',
                        message: '修改课程信息成功!'
                    });
                    //跳转到第二步
                    this.$router.push({path:'/course/chapter/'+this.courseId})
                })
        },
        saveOrUpdate() {
           //判断添加还是修改
           if(!this.courseInfo.id) {
               //添加
               this.addCourse()
           } else {
               this.updateCourse()
           }
        }
    }
}
</script>
<style scoped>
.tinymce-container {
  line-height: 29px;
}
</style>
